▎ 摘　　要

NOVELTY - Preparing manganese dioxide/nano gold/graphene-carbon nanotube three-dimensional structure nanocomposite comprises e.g. (i) dispersing carbon nano-tube in distilled water, and mixing with concentrated sulfuric acid, concentrated nitric acid, concentrated sulfuric acid, (ii) adding potassium permanganate into obtained product, reacting, then heating, solid-liquid separating the obtained product and drying to obtain manganese dioxide/graphene-carbon nanotube material, (iii) sequentially adding obtained manganese dioxide/graphene-carbon nanotube material into anhydrous ethanol, distilled water, concentrated aqueous ammonia and 3-aminopropyltrimethoxysilane, reacting, filtering and washing with distilled water to obtain aminated manganese dioxide/graphene-carbon nanotube water dispersion material, and (iv) adding nano gold glue aqueous solution into aminated manganese dioxide/graphene-carbon nanotube water dispersion material, stirring and reacting, filtering the product and drying. USE - The nanocomposite is useful for producing hydrogen peroxide electrochemical sensor (claimed). ADVANTAGE - The nanocomposite: has simple preparation method, and sandwich design which solves problem of conductivity and stability of manganese dioxide material; and the sensor: realizes hydrogen peroxide fast, sensitive and highly selective detection. DETAILED DESCRIPTION - Preparing manganese dioxide/nano gold/graphene-carbon nanotube three-dimensional structure nanocomposite comprises (i) uniformly dispersing carbon nano-tube in distilled water, then adding concentrated sulfuric acid and concentrated nitric acid, stirring at 65-75 degrees C for 2-4 hours, cooling to 0 degrees C, then adding concentrated sulfuric acid, mixing uniformly, and heating to 50-60 degrees C, (ii) adding potassium permanganate into obtained product, stirring and reacting for 2-2.5 hours, then heating to 85-95 degrees C, solid-liquid separating the obtained product and drying at 180-200 degrees C for 3-4 hours to obtain manganese dioxide/graphene-carbon nanotube material, (iii) sequentially adding obtained manganese dioxide/graphene-carbon nanotube material into anhydrous ethanol, distilled water, concentrated aqueous ammonia and 3-aminopropyltrimethoxysilane, reacting for 8-9 hours, filtering the obtained product and washing with distilled water to obtain aminated manganese dioxide/graphene-carbon nanotube water dispersion material, and (iv) adding nano gold glue aqueous solution into aminated manganese dioxide/graphene-carbon nanotube water dispersion material, stirring and reacting, filtering the product, washing and drying to obtain final product. INDEPENDENT CLAIMS are also included for: (1) manganese dioxide/nano gold/graphene-carbon nanotube three-dimensional structure nanocomposite is prepared by above mentioned method; and (2) use method of nanocomposite for producing hydrogen peroxide electrochemical sensor comprising applying 10 mu l of 5 mg/ml nanocomposite aqueous solution on clean and dry glass carbon electrode surface to obtain hydrogen peroxide electrochemical sensor.